The present invention relates to a data distribution system for distributing data to users through a communication network and, more particularly, to a data distribution system for distributing different data to users.
With the recent rapid spread of portable telephones, there have been a growing number of occasions when users perform data communications by electronic mail in mobile environments. A great deal of attention has been paid to advertisement distribution services for distributing advertisement information to portable telephones and the like by electronic mail and Web pages. For example, conventional advertisement distribution systems for distributing information to portable telephones are disclosed in Japanese Patent Laid-Open Nos. 2000-224658 and 2000-201228.
A conventional, general advertisement distribution system is comprised of an upload terminal, distribution server, and portable terminal. The distribution server, upload terminal, and portable terminal are connected to each other through a communication network such that they can transmit/receive data to/from each other. The upload terminal is installed in a sponsor's office or advertising agent or the like that operates on behalf of the sponsor and used to register advertisement data in advertisement distribution services. The distribution server is installed in an advertisement distribution center to distribute registered advertisement data to the portable terminal. The portable terminal is carried by the user to receive the advertisement data distributed from the distribution server and display it.
FIG. 11 shows the operation of a conventional, general advertisement distribution system. A sponsor creates advertisement data by itself or by requesting an advertising agent, uploads the advertisement data from an upload terminal to a distribution server, and registers it, in advance.
First of all, the user who receives advertisement distribution services uses the portable terminal to transmit user information about the user himself/herself and the portable terminal to the distribution server so as to perform user registration. After the user registration, questionnaire data is transmitted from the distribution server to the portable terminal. When the user answers the questionnaire with the portable terminal, the user information in a user information table stored in the distribution server is updated.
A questionnaire to the user contains question items for designating user's preferences and the like, and the user's preferences and the like are registered as user information in the distribution server in accordance with the answer. Thereafter, the distribution server selects and distributes advertisement data that suits the user's preferences to the portable terminal of the user. When the user's preferences change, the user transmits information about the preferences from the portable terminal to the distribution server, thus updating the user information.
According to the conventional advertisement distribution system described above, to select advertisement data that suits the preferences of each user, each user must answer questionnaires and the like. In some cases, however, no answer can be obtained, and hence advertisements that suit the user's preferences cannot be distributed. In addition, in some cases, changes in user's preferences cannot be quickly grasped, and hence distributed advertisements differ from the user's preferences.